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Author Topic: 1.6TD head on a AAZ?  (Read 1735 times)

July 01, 2019, 06:20:27 am

BajaVWCamper

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1.6TD head on a AAZ?
« on: July 01, 2019, 06:20:27 am »
Hi, what do i need to know to put a 1.6TD head on a AAZ block?.

i have a nearly new AAZ engine without a head and a 1.6TD head laying around. I see a lot of "AAZ heads on 1.6" threads but not the other way around.

On quick inspection i see it lines all up right but the timing belt is quite tight on it. do any sprockets or anything have to be changed for it to work?

Thanks!



Reply #1July 01, 2019, 10:35:08 pm

rabbid79

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Re: 1.6TD head on a AAZ?
« Reply #1 on: July 01, 2019, 10:35:08 pm »
The question of putting 1.6 heads on 1.9 blocks comes up once in a while.  In short, it shouldn't be done.  The problem lies in the small displacement of the 1.6 head's swirl chambers, specifically sized for the displacement of the engine.  It has been a while since I've done the math, but it turns into something like a 27:1 compression ratio when used with a 1.9 block!  Although, it would be interesting to see how such an engine ran.
« Last Edit: July 02, 2019, 12:55:15 am by rabbid79 »
'15 WRX
Parts for 2.0 TD build - Now looking for suitable car to put it in.

Reply #2July 02, 2019, 07:24:10 pm

ORCoaster

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Re: 1.6TD head on a AAZ?
« Reply #2 on: July 02, 2019, 07:24:10 pm »
So Knowing that you have a greater compression ratio going than stock can't retarding the timing adjust for that?  Otherwise you would have a very sharp clack going there. 

Rather than the normal 1.6 timing of 88 to 93 could you not try say 85 and see what that gives for performance and then either reduce it some more or bump it up to 88 and see what it sounds and runs like.

Just playing with those what if's in my head.

Reply #3August 08, 2019, 09:21:52 am

theman53

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Re: 1.6TD head on a AAZ?
« Reply #3 on: August 08, 2019, 09:21:52 am »
It is more than timing. The cylinder pressure gets high. Blake runs this setup and it will run, but he says it gets hot in the exhaust all the time. I wouldn't do it as the head is a downgrade. It has 2 or 3 mm smaller valves, bad breathing, and the parasitic draw of having to turn the higher compression would be a no for me.